Function:Automatically covers the soil, measures soil CO2 flux, then opens to re-expose soil to ambient conditions aftereach measurement is completed.

Measurement Technique:Time intervals, or required differential CO2 values between automatic measurements are user-set in either anopen or closed system ACE Station.

A single ADC CO2 IRGA is housed directly next to thesoil analysis area to provide highly accurate data.

Application:Worldwide, in diverse and often harsh environments.Examples from published papers include:

Tillage vs no-tillage agriculture in Slovak Republic•Mid-boreal and subarctic soils in Canada•Wheat/maize crops in China•Lawn soils in urban areas•Paddy fields in China•Antarctic vegetation•

ACE BioScientific Ltd.

Automated Soil CO2 Exchange SystemACE StationIndependent Station for automatedsoil CO2 flux measurements, data-logging and secure data storage

Soil chamber optionsSmall chamber for open mode•Large chamber for closed mode•Transparent or opaque chambers•

ACE Master ControllerUp to 30 ACE Stations may be linkedto a Master Controller, forming anACE Network

Sensors Connect multiple sensors for soiltemperature and soil moisture

ACE Station Easy to install and program:The ACE Station is easy to set up and program.

The control console features a large display screen.Programming is achieved using just 5 keys to drivea series of intuitive menus.

Data Logging:Gas exchange measurements, soil flux calculationsand sensor measurements are all displayed andrecorded by the ACE Station. Data is stored internally and can be accessed by SD card or USB cable.

Each ACE Station is a complete, fully integrated soilCO2 flux analysis system comprising a soil chamber,heat reduction parasol and arm that pivots fromthe control console, where measurements are bothdisplayed and recorded.

Each ACE Station operates independently for datacollection and logging.

An external power source with an output voltageof 12-40VDC is required. A 40Ah car battery willpower an ACE Station for around 28 days (based onmeasurement frequency of once per hour). Thepower efficient ACE Station can be poweredcontinuously by battery, with solar panel or windturbine.

Long-term unattended operation:

The automated design of the ACE Station allowsthe soil area to be exposed to ambient conditionsbetween measurement cycles.

At user-set time intervals, the chamber willautomatically cover the soil to carry outmeasurements. Once these measurements arecompleted, the chamber will automatically re-expose the soil area.

The novel “swinging arm” mechanism is proven tobe reliable, field rugged and to ensure a consistentseal when the chamber is covering the soil.

When the chamber is in the exposed position, theACE Station enters a low power consumption mode.

26 u/r

27 33.5

28 33.2

19 10.6

20 n/a

21 o/r

13 n/a

14 14.7

15 14.8

1 22.7

2 14.6

3 14.4

7 22.5

8 23.0

9 24.1

OK

10 23.34 55.3

5 22.9

6 22.8

11 23.2

12 23.0

16 55.2

17 25.2

18 24.7

25 44.2

22 11.2

23 12.4

24 33.6

30 55.6

32 u/r

29 12.7

31 44.3

C 6.6

21:07tmdt 01:09:05

Cmeas 310

record 1

Cref 230

U 250

1st-last

U170

prev

T1

next more

23.4

12.0

0.0

time0.0

time

12.0

1 22.7 7 22.5 13 n/a 19 10.6 26 u/r2 14.6 8 23.0 14 14.7 20 n/a 27 33.53 14.4 9 24.1 15 14.8 21 o/r

ok

Record 1 dt 01:06:06 tm 13:07

Cref 430 Cmeas 474 �C 44

U 230 NCER 17.0 T1 23.4

1st - last prev next more

1 22.7 7 22.5 13 n/a 19 10.6 26 u/r2 14.6 8 23.0 14 14.7 20 n/a 27 33.53 14.4 9 24.1 15 14.8 21 o/r 28 33.24 55.3 10 23.3 16 55.2 22 11.2 29 12.75 22.9 11 23.2 17 25.2 23 12.4 30 55.66 22.8 12 23.0 18 24.7 24 33.6 31 44.3

25 44.2 32 u/r

2

Open and Closed system modes:

ACE Stations are available in either a closed or an open system configuration.

In both measurement modes, with the chamber in the covered position, a ΔCO2 value is determined fromthe difference between the reference gas entering the chamber and the analysis gas within the chamberat the end of the experiment.

Transparent versions of both the open and closed chambers are available for measuring net CO2 exchangewithin the chamber area. In applications of high photosynthetic activity, open mode transparent chambersare recommended.

Flux, moisture and temperature data:Soil flux is expressed as Net CO2 exchange rate (NCER) in µmol m-2 sec-1..

In addition to the CO2 exchange data a PAR sensor is provided, mounted on the ACEStation chamber.

As many as 6 soil temperature sensors and 4 soil moisture sensors may also be directly connected to each ACE Station. Sensor measurements are displayed andrecorded alongside the gas exchange and soil flux data.

Automatic calibration:Every ACE Station is fitted with Zero/Ambient CO2 concentration re-calculation for accurate NCER values.

3

Open Mode:

When the chamber seals, ambient air is passed through the smaller 1.0L chamber at a controlled flow rate.

Soil CO2 flux is then determined at equilibrated conditions within the chamber.These measurements, although slower, are regarded as more accurate by manyresearchers as they are less influenced by changes within the enclosed chamber or variations in the soil structure.The open chamber is designed with a pressure release valve and fan to minimiseany internal pressure gradients.

An open system ACE Station may also be used in a closed mode by fitting a closed system chamber head.

Closed Mode:

A measurement is made once the chamber is sealed. CO2 inside the large 2.6Lchamber will then increase according to soil activity. The rate of soil flux isdetermined from the ΔCO2 after a user-defined time interval.

These measurements are simple and fast.

ACE NetworkAlthough an ACE Station will functionindependently at a single sample location, it is typical that a number of Stations will be used incombination, as a Network deployed across a field site.

As many as 30 ACE Stations can be connected together in an ACE Network via an ACE Master control unit. This Master control unit will supply power to and collectdata from all Stations within the network.

The ACE Master control unit is connected to each ACE Station by electrical cable only. Each ACE Stationcan be a maximum of 100 meters away from the Master control unit.

Individual ACE Stations can be removed from, or added to, the ACE network without interrupting datacollection.

ACE MasterThe ACE Master control unit is a waterproof, steel enclosure featuring a graphic display, CompactFlash carddrive, a maximum of 30 ACE Station docking ports and 2 battery ports.

ACE Master control unit is available in 3 options with either 10, 20 or 30 ACE Station docking ports.

Programming control of an ACE Network is achieved using just 5 keys to drive a series of intuitive menus.

The ACE Master control unit monitors all Stations within the experimental network and flags any problemsencountered.

The graphic display may be used to review and plot experiments in the field. For example:

One Station, all parameters, one time point•One parameter, one time point, all Stations•One Station, one parameter, all time points •

Power is via 12V or 24V batteries or a suitable alternative supply.

4

Options and Accessories:At ADC BioScientific, we recognise that everyapplication is unique and has specifications, such asthe ability to extract gases from the soil chamber forlaboratory analysis. We are always willing to discusssuch requirements.

A comprehensive range of the most commonlyrequired accessories are available for ACE Stationsand ACE Networks.

Transit case•Mains supply kit with 50m DC power cable•100m DC power lead for use with 1 ACE Station•Soil moisture sensors by Delta T Devices•Soil temperature thermistor probes•Additional soil chambers•

Comprehensive installation kits, spares kits andmanuals are supplied as standard.

Applied to worldwide research:

Measuring CO2 efflux from agricultural soil in relation to tractor wheel traffic and the amount of manureapplied to the soil (Altikat et al., 2018).

Monitoring CO2 land/atmosphere flux in the High Arctic, Svalbard to further our understanding of factorsaffecting CO2 fluxes in sensitive ecosystems in the Arctic (Cannone et al., 2019).

Measuring CO2 flux between the atmosphere and the maize field fertilized with digestate from anagricultural biogas plant (Czubaszek, Robert 2019).

Measuring the carbon capture efficiency, yield, nutrient uptake and trafficability of different grass specieson a cultivated peat soil (Berglund Ö, Berglund K, Jordan S, Norberg L, 2019).

Application Notes include:

“Setting the timing of closed mode measurements with an ACE Station”•“ACE Station operates for up to 28 days from a single 40Ah battery”•“Extracting gas samples from an ACE Station for the analysis of soil CH4 and N2O flux”•“Extending the air inlet to prevent water ingress (in areas prone to flooding)”•“Measuring CO2 efflux from agricultural soil”•

A list of citations and set of application notes are available to request from:www.adc.co.uk sales@adc.co.uk

or a local support centre

5

Technical SpecificationsACE Station

Measurement of CO2:

Measurement of PAR:

Measurement of soiltemperature:

Measurement of soilmoisture:

Flow control to chamber:

Flow control accuracy:

Display:

Programming:

Recorded data:

Internal battery:

Power supply:

RS232 output:

Electrical connections:

Dimensions:

Closed chamber volume:

Open chamber volume:

Soil collar diameter:

Weight:

Master Control UnitConstruction:

Electrical Connections:

Display:

Programming:

Recorded data:

RS232 output:

Power connection:

Dimensions:

Weight:

Standard range nominally 40mmol m-3

(0-896ppm at standard temperature andpressure) 0.05mmol m-3 resolution (1ppm).Infrared gas analyser housed directly adjacent to soil chamber. Differential open or closed system.

0 - 3000µmol m-2 sec-1. Silicon photocell

6 selectable inputs for thermistors

4 selectable inputs for commercially availablesensors.

200ml to 5L min-1

+/- 3% of FSD

240 x 64 dot matrix LCD

Each ACE station has a user-friendly interfacedriven by only 5 keys

Removable SD card. Micro USB port.

12V standby 1.0Ah battery back up(Networked Station only)

External battery, solar panel or wind turbine.One 40Ah car battery provides power for ca.28days of continuous use

User selectable rates of up to 19200 baud

Robust, waterproof 3 pin and 5 pin RS232

82 x 33 x 13 cm

2.6L

1.0L

23cm

9.0 kg

Steel electrically sealed enclosure

30 ACE Station docking ports

Graphic 240 x 64 dot matrix LCD

User-friendly interface driven by only 5 keys

Dual Compact Flash card drive

User selectable rates of up to 19200 baud

100 - 240 VAC. Dual 12V battery ports.

40 x 40 x 20 cm

12.0 kg

For the investigation of plant, soil andatmospheric interactions,

ADC BioScientific Ltd. expertly produce awide range of portable, user-friendly

and cost-effective devices, fromphotosynthesis to soil respiration

systems. We are committed to enablingcarbon cycle research worldwide

through quality instrumentation andlocal, technical support.

ADC BioScientific Ltd. also supply: PortablePhotosynthesis Systems, Leaf Area Meters,

Chlorophyll Content Meters, AdvancedFluorometers, Automated Soil CO2 ExchangeSystems, Portable Soil Respiration Systems

and Field Gas Analysers.

ADC BioScientific Ltd.Global House Geddings RoadHoddesdonHertfordshireEN11 0NT

CONTACT US:

www.adc.co.uk+44 (0) 1992 464527sales@adc.co.uk www.adc.co.uk

Courtesy of The University of Vermont, Kenya